Help me ad 10-15 mph to the way cool electric moped

Well, the beauty above isn't quite mine yet, but I hope it soon will be. I'm working with an electric scooter vendor in San Diego to configure the above emoped to my needs, and I could use some advice from the forum. Currently this bike has a big heavy 60V 12AH silicon battery that goes about 28 miles between charges and a 450W rear hub motor that gets it up to 20 mph. That's not quite good enough for me to be able to ride with my local moped gang, whose gas mopeds average 25-35 mph on rides up to 40 miles in length.

Sooooo, my simple goal is to configure the emoped so it can go at least 30 mph, preferably 35 mph, for a range of up to 40 miles between charges, preferably 60 miles (so I can drive it to work and back 12 miles every day for a week without recharging it).

My vendor and I are sorting through ideas to make this happen, and so far are thinking of:
-- switching out the heavy silicon battery pack for lighter, dual lithium long-range battery packs. I already own one such battery (52V BYI Super Lithium Polymer, 10 amp hour with 35 amp gateway & 25 amp hi-power BMS, Soft Pack technology) so I may just need to get one more.
-- adding solar panels for incremental charging along the route and while stopping for breaks
-- more powerful rear hub motor
-- more robust controller to handle the bigger motor

If anyone has more specific tactics to help the emoped reach 30-35mph for 40-60 miles between charges, let me know, along with how much extra you think it'd cost. I appreciate it!

Is it really that hard to add a mere 10-15 mph speed and 20-40 miles of range to a simple electric moped like this? The vendor is going to swap out the silicon battery pack for a lithium one today and test the speed. Maybe just that step will lighten the bike enough to get it up to 30 mph and increase the range -- we'll see.

I want to apologize. I shouldn't have called the Vectrix a big ugly toad. I respect all companies trying to make cleaner, more sustainable vehicles. I've seen a Vectrix once and actually thought it was pretty cool looking -- it's just not what I want to take along with my classic- moped-riding gang.

Mik: I have read in many places that many electric bikes and bike-type vehicles are artificially limited to 20 mph so as not to run afowl of various state DMV laws pertaining to maximum allowed speeds of electric bikes. That is what led me to believe that it would not be too hard to bump up something like the electric moped I'm considering by 10-15 mph. It may put the vehicle in a grey area with the law, but I'm prepared to deal with that. I am interested in knowing the simplest route to make it happen from a technology/mechanical standpoint.

I think it would be easier to modify a well known XB-600 to get to your desired specs. It's been done before...take it up to 72 volts, shunt mod, upgrade mosfets and capacitors...add more/better batteries to hit range.

You are already at 60 volts with this bike so there isn't the same potential increase in speed like when you take a XB 600 from 48 volts to 72 volts.

Plus you are starting with a 450 watt motor rather than 600 watts. That might not be enough to ever go 35 mph.

Plus this bike...you don't even give a name: Brand? Model?...so it's components might be little known and you would be very much on your own...in contrast many people have successfully modded a XB-600 and you could just follow their guides.

Eltoro,
I hate to be repetitive, but get an e-moped and start riding instead of experimenting. That way you're legal, and fast, and riding and stopping with hydraulic discs front and rear. Again I'll recommed the Emoto line as they genuinely get 30 miles on a charge, go 30 if you want em too and have exceptional brakes. Great acceleration too. I've had test riders comlain that they are too fast off the line. These will embarrass to nasty little 2stroke with their CVTs. Over the last 2 years I've put almost 2000 hard miles on a pair of em and do nothing but air em and charge em. None of my customers have had to do anything either. And the G2 has a nice retro look to it. Mine are G3's.
As I said, I sell em because they work, and will do what you ask-right out of the crate.

Eltoro,
The web site is www.emotoev.com. BTW, the G4 is discontinued. The others range from 2599 to 6599 to the g6 motorcycle. Shipping would be determined by the selling dealer. If you would like more information about our dealership, contact me privately. Thanks for taking the time to investigate my suggestions. jth

Regarding comments so far, I think that eltoro is really looking to stay with a classic (and inexpensive) "true" moped style bike.

As far as increasing the speed, it depends if speed limitation is due to:

1. An electronic speed limiter in controller,

2. The motor's maximum free-running speed which is governed by the maximum voltage to the motor, or

3. The motor simply does not produce enough torque to propel the moped faster, even at a speed well below the maximum free-running speed.

If 1, the speed limiter needs to be bypassed. sometimes it is done by just removing a jumper on the circuit board. but if not, it will be difficult - you will need a schematic of the controller circuit and some electronics skills.

If 2, the battery pack can be upgraded to 72 volts, but the controller components, usually the power MOSFETS and filter capacitors have to handle the extra voltage, or be replaced with ones that can. Remember that a fully charged "72 volt" battery pack (either lead acid or lithium) may be as high as 89-90 volts.

If 3, the controller's current limiter can be raised, a lot of people have done this by reducing the resistance of a low value shunt resister that is used to measure the current. Lots of articles on doing this in this forum. Do a search using the words "shunt mod".

The voltage or current changes will probably push the hub motor beyond its fairly low 450 watt current limitation, but a lot of hub motors are conservatively rates - especially if you are not in a hot climate. So you may be OK, but don't try any of these mods unless you can accept burning out a motor, or a controller.

Something that everyone seems to forget is that power required increases with the cube of the speed (neglecting rolling resistance). To go nearly twice as fast as you need to do, you need 8 times the power. If the 450 watt hub motor is correctly sized now, then you really need a 3.6 kW hub motor. There may be enough meat in the existing hub motor to get it to 600 watts, but the massive increase you need really means that you need to replace it. Likewise the controller will not put out nearly 10 times the power, so you need to replace that as well. When you're replacing the batteries you will also need 8-10 times the capacity. You want to go twice as far at twice the speed, that's 8 times the total energy.

If you're going to get a charge along the way from solar then you will need flexible solar panels that you can unroll or unfold. If you're drawing 3ish kW for a bit over an hour you could say your battery was about 3.0 kWh. To get a 20% topup charge during an hour break in full sun you'd need 600 watts. That's about 6 square metres of folding solar panel! The size of a car parking spot. You'd need five of these: http://www.ctsolar.com/64WBlueFoldingSolarPanel.aspx

Regarding your observations that Eltoro is looking for an inexpensive and classic Moped:

Remember some of his design parameters: at least 30 mph and 30+ miles per charge. I too want the same so I can provide my clients with an incredible value with timeless styling. What I don't want to do is present some drum braked, underpowered, marginally manufactured LSEB as a mule for throwing money at so that he can be unsuccessful, disappointed and climbs back in his car instead of enjoying two wheels. Based on his comments, he (and seemingly his dealer) seem unprepared and/or ill equipped to perform a major makeover. And in the process, the word inexpensive gets tossed out the windown. Even if he magically does what manufactures seem unable to do, he is still stuck with a marginal chassis. Sorry, but perfume on a pig stil leaves the pig. One very expensive pig.

Yes, my parameters: at least 30 mph, at least 40-mile range, and a respectable-looking, moped-style scooter. Used classic-style mopeds can be bought in good condition for anywhere from $100-$1,000. They get up to 125 mpg and go between 25-45 mph. We're talking true classics like the Honda Hobbit, Sachs, Puch, Tomos, Motobecane, Peugot, Piaggio Ciao, etc. That's how the peeps in my local moped gang roll. I want to show them that a clean electric moped can look cool, fit in with their bikes, keep up, and go at least 40 miles before needing a charge, which is about the outer limit of their weekend rides. Is it REALLY that impossible to find a cool retro-looking electric moped that can do at least 30 mph for 40 miles for $1,000 or under? The fact that is seems so hard to find is illustrative of perhaps a major reason that electric vehicles are not being adopted by more people. How discouraging.

"Is it REALLY that impossible to find a cool retro-looking electric moped that can do at least 30 mph for 40 miles for $1,000 or under? The fact that is seems so hard to find is illustrative of perhaps a major reason that electric vehicles are not being adopted by more people. How discouraging."

I can't imagine that you could buy the batteries alone that would do that for any vehicle for under 1000 dollars. 30 mph for 40 miles is quite close to the range of a Zero S/DS. (I got 45 miles at about 25 mph on the flat to the flashing low battery warning) The battery for my bike costs 5000 dollars... If you figure out how to get equivalent batteries for roughly 1/10th of that price please let us know where!

Currently this bike has a big heavy 60V 12AH silicon battery that goes about 28 miles between charges and a 450W rear hub motor that gets it up to 20 mph.

Just examine that statement for a moment. 60 volts times 12 Ah gets you 720 Wh. If the 450 watt motor draws 450 watts at full speed, then it will use 720 Wh in 1.6 hours and cover 28 miles. So it all looks Great!

The 12Ah battery being a lead acid will be rated at the 20 hour drain rate. Draining it completely in just over an hour it will probably produce an actual 10 Ah or less. So that's 600 Wh. If you drain it much below 50% you'll destroy the battery in short order. So that leaves you with 300 Wh. The voltage will sag a bit under that sort of load and so the available energy will fall again. Perhaps 280 Wh. So you'd be lucky to ride flat out for more than 35 minutes (unless you're happy to wreck the battery) and you'd only cover 12 miles. That's assuming that you never need to brake. Every time you use the brakes the energy goes into them instead of moving the bike. Also assuming that there is no headwind. Headwinds at these low speeds make a huge difference. A gentle 10 mph headwind will cut your range to less than half or less than 6 miles. That should give you an idea of how far you need to go to reliably get to 40 miles at 35 mph. It's a huge upgrade not a minor tweak.

"So, how sad, you pay $1,600 and you STILL can't keep up with your gas-powered moped friends who payed $100-$1,000 for their rides and get 100-125 mpg."

You can look at it that way and be sad or you can look at it another way.

I drive something like a modified XB 600 every day from April to Novemeber. I don't pay for gas or insurance and the millage equivilent is much better than 125 mpg. Three years and I am on the same batteries. The bike paid for itself in two years.

You also need to increase your comparison numbers. That's a new electric scooter. A new Tomos moped is $1000 to $1700.

DB, how fast does your modified XB 600 go? If I could modify one to go 30-40 mph I might consider that. What did you do to modify yours? You see, I already have a folding electric bike that can go about 20 mph, so I have no need to get an electric scooter/moped unless it can carry me in the 30-40 mph range. Thanks!

Yeah, lithiums are better. Every battery has a sort of limit to it. If you could imagine just putting wheels on the battery and a little motor and sending it off down a track, every battery will go a different distance. The large heavy low capacity lead batteries will go the shortest distance. The small light energy dense lithiums go further. Those are sort of the limiting condition. There's no way you can design something powered with lead that will go further than that limiting condition. Everything you add makes it go a shorter distance and adding batteries can't help because that's the limit for that type of battery. However by changing to lithium you can go further. They're lighter, the capacity is higher and they can be more deeply discharged without damaging them.

Designing an electric vehicle is a major challenge. Handicaping yourself with parameters like making it look like a particular style of vintage bike and under a certain dollar value (under the second hand price of the cheapest motorised vehicles ever built) makes for a *very* challenging design. I don't think it's possible but I've been wrong before. It might be possible and if you can do it, wow, I'm super impressed!

You mentioned that you take a break part way through the ride. If that break is at a cafe (as I'd imagine) then try talking to the owner of the cafe. You bring a lot of business to him, perhaps he'd be happy to let you recharge. That would halve your challenge right there. All you need is a powerful charger. Sadly a good charger is going to be more than half your budget, but hey, somethings got to give! Look on the other side of the coin, there's going to be no servicing, no oil, no filters, no pistons or rings, no clutches or spark plugs. More spent up front but perhaps less in the long term? That's how it's working out with the Zero. The equivalent motorcycle needs a full rebuild every 15 hours of operation. I've already saved 1000 dollars in service costs in my first 1000 miles.

Or you might be able to do what the Zero XU does. Have a second battery and charger. Make the battery a quick change unit. You could swap batteries at the cafe and put the discharged one on a cheap slow charger. Next weekend you swap again. (depends if you know the cafe owner well enough to ask him if you can leave a battery there float charging all week)

You could also add a bicycle trailer stuffed with batteries. That would increase the range and leave the bike it'self looking cool. Or you could put hub motors on the trailer as well and get more speed that way. There are *big* hub motors available. If someone wants to test your bike, just unclip the trailer and it's a stock bicycle again.

If the task looks impossible you need to avoid a brute force solution and look for ways around the problem.

DB, how fast does your modified XB 600 go? If I could modify one to go 30-40 mph I might consider that. What did you do to modify yours? You see, I already have a folding electric bike that can go about 20 mph, so I have no need to get an electric scooter/moped unless it can carry me in the 30-40 mph range. Thanks!

XB 600's can go about 30 mph with a 60 volt mod and 35 mph with 72 volt mod.

I could go 20 miles when the batteries were new...not sure what others do.

If you have an electric bike why don't you just mod it to 25 or 30 mph and add some batteries to extend the range?

$50 or $200 might give you the parts for most of what you want. It might be as simple as adding another 12 volt battery.

To go nearly twice as fast as you need to do, you need 8 times the power. If the 450 watt hub motor is correctly sized now, then you really need a 3.6 kW hub motor.

Actually, assuming 9 ft^2 frontal area, and a conservative coeff. of drag of 1.0, about 1.9 kw would be needed to propel the moped at 35 mph on level ground. I know of e-bikers who soup-up their ordinary e-assist bicycles to go 50 mph or more - with hub motors with factory ratings mot a lot higher than 450 watts. Sounds dangerous to me, but they do it. So, it is certainly possible to fix up a Puch-style moped to go 35 mph. I suspect a new controller will be required at a minimum, though.

I was thinking of twice as fast, 40 mph. That would be 2.8 kw to the ground with your figures. If the motor is 85% efficient (not unusual) that would be drawing 3.3 kW. (remembering that electric motors are generally rated by what they consume rather than what they produce) Less than my quick and dirty estimate of 3.6 kW but not all that far off. Whichever way you cut it, it's still a big ask for a motor to output 4-8 times it's rated power.

pardon, but with a 450 watt motor, your not going to be able to add much more speed, even if you improve the batteries and controller. That 450 watt motor would get super hot, too. You need around 1000 watts on an ebike to get 30 mph. On a heavier moped with smaller wheels, you would need even more.
My advise: find a motor with alot more magnets than the 450 watt motor. Maybe you can add magnets? no.
The weight of the moped and those 22" rims are slowing you down bigtime. But you need the 22" rims for climbing (more torque). Get a 1500 watt rear hub maybe a new controller and 72 v 25 ah lithium.
You just as well buy another bike? The upgrades needed greatly exceed the value of this emoped.

I run 36 & 48 volts on my e bike kit. My hub motor can handle maybe 90 volts.
I've never heard of somebody (until now) running 35 mph with a 450 watt direct drive gearless hub.
The wattage rating must be arbitrary. Also, my 750 watt hub has a peak of 1200 watts w/ 48V.
what's the weight on a moped? 150?
I agree that there is "overhead room" with repect to motors, but not always so with the controllers.
thicker wiring can used, also